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Here in Texas, its already starting to warm up. I have a 250sq/ft media room located above my garage. The room has two registers located about 3.5' up on one wall. When the house was built one yr ago, there was no Return put in that room. I am already planning to put a return in. My question is what the benefit would be to install a in-line duct fan in my return, to either be able to switch on or off, or have it on a seperate tstat. My understanding is that this would pull air from the room forcing it back into the system and then out through all of my returns in the house. Im hoping this would help in keeping the temperature between both floors at a more constant temperature. I would appreciate any help or suggestions on this matter.

I hate to be the bearer of bad news. But you are never going to regulate this room comfortably. Nature is working against you. The lower level will cool down before it gets cool in the upstairs room. If you set the stat way lower it will just freeze you out downstairs. You may want to try a window unit. Or even one of those PTAC units like in a motel room. I don't think adding a return or a booster fan, would give you any noticable diffrence for the amount of money you would spend having them installed. You could try one of the Sanyo or Mitsubishi mini splits, probally the most practacal solution since the space is fairly small. They are kind of exspensive, but work pretty well in situations like this. Or you could have a zoning system installed on your exsiting system assuming it is large enough to carry the extra load. They are kind of exspensive to install also, but they work well. I like Carrier's Comfort Zone 2. It will work on anything if installed correctly with the right suply dampers and a properly sized and balanced bypass damper.

duct tape and cable ties will fix anything, if that don't work add a 90-340.

Go with a mini split. My office is similar and the load is so different from the rest of the house. The zone is too small and too far down the trunk to consider zoning. Leave the exsisting ducts alone and use the min-split when additional cooling is needed. Adding the return may also help but skip the fan.

Humidity concerns

>>Leave the switch on the thermostat for the fan in the on setting not auto.

That suggestion is a double edged blade. It *will* help with temperature control. Also, it *will* migrate humidity from the coil back into the house air, rather more than "auto" will. There have been studies done at the Florida Solar Energy Center (FSEC) which document perhaps a change of 10% in relative humidity from the fan being "on" vs. "auto".

You didn't say where in Texas but if your summers are humid, this move will put you into a higher indoor humidity. If summers are dry it might not be a problem.

There are several devices which cycle your A/C fan on intermittently, some of them are smart enough to not aggravate your humidity problem, but I do not believe they would be a solution to this problem. After all this is a hot-weather problem when your AC fan will be running a large percent of the time anyway.

Thanks

I appreciate all of the feed back on this thread. I am currently looking into the mini-splits. I went ahead and put in a 8inch return for the room. The room is well insulated, walls and ceiling are blown cellulose floor is bated. How will running the AC on ON instead of AUTO effect utilities since the fans going to run near constantly? Again, thank you guys for taking ur time to lend me some advice.

Not much in simple motor costs, but every time it shuts the condenser off, you reintroduce moisture back into the air from the warm damp coil and risk water blow off. Now your system capacity is reduced as it has to deal with moist air (increased latent load). It wont help your problem any though. The mini split is your answer.

Re: Thanks

Originally posted by stogy I appreciate all of the feed back on this thread. I am currently looking into the mini-splits. I went ahead and put in a 8inch return for the room. The room is well insulated, walls and ceiling are blown cellulose floor is bated. How will running the AC on ON instead of AUTO effect utilities since the fans going to run near constantly? Again, thank you guys for taking ur time to lend me some advice.

Check those batts to see if hot attic air can circulate between the batts and the floor.

If you have floor trusses they need to be sealed and insulated ,from the attic.